Reagent well having a retention feature for retaining a lyophilized reagent

ABSTRACT

An article for performing a reaction includes a reagent well having a side wall, a bottom wall and an open upper end. A lyophilized reagent is retained within the well by a non-integral retention feature that is inserted into the open upper end of the well and fixed to a side wall above the reagent. An opening in the retention feature is smaller than a diameter of the reagent, but is sized to permit a pipette tip to be inserted into the well. The retention feature may be a collar fixed to the side wall and may include fingers extending axially into the well. The well and the retention feature may be correspondingly tapered. A method for reconstituting a lyophilized reagent includes the steps of drawing into a pipette tip attached to an automated pipettor an amount of a diluent and dispensing the diluent into the reagent well to thereby reconstitute the lyophilized reagent.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit under 35 U.S.C. §120 of the filingdate of non-provisional patent application Ser. No. 14/210,127 filedMar. 13, 2014, which claims the benefit under 35 U.S.C. §119(e) of thefiling date of U.S. Provisional Application No. 61/782,320, filed Mar.14, 2013, which is incorporated herein by reference.

BACKGROUND Field

The present disclosure relates to systems and apparatuses for performingautomated reagent-based biochemical assays.

Background Information

Automated molecular assay instrumentation offers numerous advantages,however most automated instruments suffer from a limited set of assaycapabilities. These limited capabilities complicate or inhibit parallelprocessing of multiple assays and, as a result, reduce sample throughputand flexibility in assay choices. This is particularly true forsensitive assays such as those involving nucleic acid detection and/oran amplification procedure. There are many procedures in use foramplifying nucleic acids, including the polymerase chain reaction (PCR),(see, e.g., Mullis, “Process for Amplifying, Detecting, and/or CloningNucleic Acid Sequences,” U.S. Pat. No. 4,683,195),transcription-mediated amplification (TMA), (see, e.g., Kacian et al.,“Nucleic Acid Sequence Amplification Methods,” U.S. Pat. No. 5,399,491),ligase chain reaction (LCR), (see, e.g., Birkenmeyer, “Amplification ofTarget Nucleic Acids Using Gap Filling Ligase Chain Reaction,” U.S. Pat.No. 5,427,930), strand displacement amplification (SDA), (see, e.g.,Walker, “Strand Displacement Amplification,” U.S. Pat. No. 5,455,166),and loop-mediated isothermal amplification (see, e.g., Notomi et al.,“Process for Synthesizing Nucleic Acid,” U.S. Pat. No. 6,410,278). Areview of several amplification procedures currently in use, includingPCR and TMA, is provided in HELEN H. LEE ET AL., NUCLEIC ACIDAMPLIFICATION TECHNOLOGIES (1997).

Automated molecular assays incorporate the use of consumable components,which may or may not hold reagents utilized in the molecular assay to beperformed, which can be manually loaded onto automated instrumentation.Providing such consumable components that are configured to limitcontamination, enhance target detection, simplify loading into andtransport within the system, enhance the operability of mechanicalcomponents within the automated system while lowering cost, andproviding high performance in connection with the assay to be performedis desirable.

The present disclosure addresses these and other needs in the art.

All documents referred to herein, or the indicated portions, are herebyincorporated by reference herein. No document, however, is admitted tobe prior art to the claimed subject matter.

SUMMARY

The present disclosure relates to systems, methods, and apparatuses forperforming automated reagent-based biochemical assays.

Accordingly, in an aspect of the present disclosure, there is provided asingle-piece receptacle. The receptacle includes a body having agenerally cylindrical upper portion and a tapered lower portion, theupper portion having an open end and the lower portion beingclosed-ended, an annular ring formed on an outer surface of the body,the annular ring separating the upper and lower portions of the body, alip circumscribing the open end of the upper portion, the lip beingadapted for inter-locking engagement with a mated cap, and a pluralityof longitudinally oriented grooves formed in an inner surface of theupper portion of the body and situated between the open end and theannular ring. In various embodiments, the closed end of the lowerportion may be flat or curved. The number of grooves disposed on theinner surface of the upper portion is selected from the group consistingof 2, 3, 4, 5, 6, 7, and 8. The lip may radially-extend from an exteriorsurface of the upper portion and tapers towards the open end thereof.

In another aspect, the disclosure provides a cap securable to thesingle-piece receptacle. The cap includes a lower portion having anouter surface for sealing engagement of an inner surface of the openupper end of the body, the outer surface including one or more annularring(s), an upper portion having a length, an inner surface, an outersurface, and an open end configured for engagement with an automatedpipettor, and further including one or more recess(es), which can beconcave in shape, disposed on the outer surface thereof extending alongat least part of the length of the upper portion, and one or more linearrib(s) disposed on the inner surface of the upper portion, each linearrib having a length corresponding to the length of at least one of therecesses, and wherein each of the one or more linear ribs is positionedon the inner surface of the cap in a manner that corresponds to at leastone of the recesses such that at least one linear rib lies on an innersurface of the cap that directly opposes the position of at least onerecess on the outer surface of the cap, and a lip positioned between,and extending radially away from, the upper and lower portions, the lipincluding a plurality of locking arms extending toward the lower portionof the cap for securely engaging the lip of the receptacle. In variousembodiments, the number of linear ribs corresponds to the number ofrecesses in a one-to-one relationship, and the number of recessesdisposed on the outer surface of the cap is selected from the groupconsisting of 2, 3, 4, 5, 6, 7, and 8. The lower portion of the cap mayinclude 1, 2, or 3 annular rings for sealing engagement of the innersurface of the body of the receptacle.

In certain embodiments, the locking arms comprise a snap fit attachmentfor securely engaging the lip of the receptacle. The number of lockingarms may be selected from the group consisting of 1, 2, 3, 4, 5, 6, 7,and 8. In addition, the number of linear ribs disposed on the innersurface of the upper portion of the cap may be selected from the groupconsisting of 2, 3, 4, 5, 6, 7, and 8. The distal portion of the cap mayfurther include a bottom separating the upper portion of the cap fromthe proximal lower portion of the cap. In certain embodiments, thebottom is scored for piercing. The at least one of the linear ribincludes a portion that gradually tapers radially inward toward thecenter of the upper portion, or increases in size (e.g., an increase inthickness or radial geometry) as the at least one of the linear ribsapproaches the bottom separating the upper portion of the cap from theproximal lower of the cap.

In another aspect, the disclosure provides a method for the automatedremoval of a cap from a capped reaction receptacle. The method includesproviding a single-piece receptacle comprising a body having a generallycylindrical upper portion and a tapered lower portion, the upper portionhaving an open end and the lower portion being closed-ended; an annularring formed on an outer surface of the body, the annular ring separatingthe upper and lower portions of the body; a lip circumscribing the openend of the upper portion, the lip being adapted for inter-lockingengagement with a mated cap; and a plurality of longitudinally orientedgrooves formed in an inner surface of the upper portion of the body andsituated between the open end and the annular ring; and a cap securableto the single-piece receptacle, comprising: a lower portion having anouter surface for sealing engagement of an inner surface of the openupper end of the body, the outer surface including one or more annularring(s); an upper portion having a length, an inner surface, an outersurface, and an open end configured for engagement with an automatedpipettor, and further including one or more recess(es) disposed on theouter surface thereof extending along at least part of the length of theupper portion, and one or more linear rib(s) disposed on the innersurface of the upper portion, each linear rib having a lengthcorresponding to the length of at least one of the recesses, and whereineach of the one or more linear ribs is positioned on the inner surfaceof the cap in a manner that corresponds to at least one of the recessessuch that at least one linear rib lies on an inner surface of the capthat directly opposes the position of at least one recess on the outersurface of the cap; and a lip positioned between, and extending radiallyaway from, the upper and lower portions, the lip including a pluralityof locking arms extending toward the lower portion of the cap forsecurely engaging the lip of the receptacle. The cap is securely engagedto the single piece receptacle. The method further includes performingan automated motion of contacting an inner portion of at least one ofthe plurality of locking arms with a raised annular ridge defined arounda receptacle slot, wherein said contacting urges the locking arms awayfrom the lip of the receptacle thereby disengaging the cap from thereceptacle, and while the cap is disengaged from the receptacle,performing an automated motion of lifting the cap away from thereceptacle, thereby removing the cap from the capped reactionreceptacle.

In another aspect, the disclosure provides a multi-well tray for use inan automated process. The multi-well tray includes a base having a topsurface, a card insert having a first surface, the card insertconfigured for removable attachment to the base, wherein when attachedto the base, the first surface of the card insert is substantiallyparallel to and flush with the top surface of the base, and a pluralityof sets of wells. Each set of wells includes a first well disposed in anopening of the top surface of the base, the first well being configuredto receive a receptacle cap, second well disposed in an opening of thetop surface of the base, the second well being configured to receive areceptacle, wherein the receptacle cap and the receptacle are configuredfor secure engagement with each other, and a third well disposed in anopening of the first surface of the card insert, the third wellcontaining a lyophilized reagent. The wells of each set of wells aredisposed in alignment with each other, and the third well is sealed witha frangible seal. In certain embodiments the third well may include oneor more retention features for retaining a lyophilized reagent at thebottom thereof.

In another aspect, the disclosure provides a reagent-containingmulti-well tray for use in an automated process. The multi-well trayincludes a base having a top surface and a plurality of wells disposedtherein. Each of the wells may be defined by a cylindrical or conicalwall, an open upper end, and a bottom. The wells may be disposed inalignment with each other, and sealed with a frangible seal. In certainembodiments each of the wells may include at least one retention featureto retain a lyophilized reagent therein. The multi-well tray may furtherinclude a lyophilized reagent disposed within each well, positioned at,or adjacent to, the bottom. Exemplary retention features include, butare not limited to, an annular ridge formed on the well wall andpositioned above the lyophilized reagent, a spiral channel formed alonga length of the well wall and positioned above the lyophilized reagent,a tapered ring attached to the well wall and positioned above thelyophilized reagent, a capillary insert attached to the well wall, and acollar attached to the well wall at or proximal to the open upper end.The collar may further include one or more fingers formed on a bottomsurface thereof that protrude along a radius of curvature toward anaxial center of the well. The capillary insert may include an open upperend that tapers toward the bottom of the well, and a capillary channelformed between the open upper end and the bottom of the well. In certainembodiments, the lyophilized reagent is held in position at, or adjacentto, the bottom through the use of electrostatic force.

In various aspects, any of the multi-well trays may also include machinereadable indicia positioned on the base or card insert containingidentifying information regarding the multi-well tray or card insert,including reagents contained therein. The machine readable indicia maybe a barcode, 2D barcode, or a radio frequency identification (RFID).

In addition, the multi-well tray may include one or more locking armsdisposed on the card insert for locking engagement with the base. Thefirst well may be defined by a first side wall and a bottom surface, andinclude a protrusion extending from a center of the bottom surface ofthe well toward the top surface of the base for frictional engagementwith a hollow portion in the lower portion of the receptacle cap. Thefirst well may also include a plurality of tabs protruding from thefirst side wall for securely engaging the receptacle cap. The secondwell may be defined by a second side wall and a second bottom, thesecond bottom including a through-hole extending from an inner surfaceof the second well to an outer surface of the base. An annular ledge maythen be formed within the second well at the circumference of thethrough-hole. The second well may also include a plurality of legsprotruding from the second side wall for securely engaging the distalportion of the cap. The third well may be defined by a third side walland a third bottom, and include one or more features selected from thegroup consisting of a convex groove, a concave groove, and a set ofgrooves comprising a criss-cross pattern disposed in the third bottom.The third side wall may be conical, tapering toward the bottom thereof.The third well may also include a plurality of rigid guides radiallyprotruding from the third wall toward a center thereof. The base may bespatially indexed such that an automated pipettor can accuratelyidentify and/or access any of the plurality of wells when the multi-welltray is placed in an automated system.

In another aspect, the disclosure provides a cartridge withcommunicating wells for use in an automated process. The cartridgeincludes a casing having a top surface, a fluid chamber disposed withinthe casing, and wherein a first opening is provided in the top surfaceof the casing having at least one side wall surface extending to, oroptionally forming at least a portion of, the fluid chamber, and a fluidreservoir disposed within the casing adjacent to and in fluidcommunication with the fluid chamber. In certain embodiments, thecartridge also includes an oil reservoir disposed within the casing andadjacent to the fluid chamber. The fluid communication between the fluidchamber and the fluid reservoir may be both liquid and gaseouscommunication, and may be provided by the same or different means. Thecartridge may also include a second opening that is provided in the topsurface of the casing having at least one side wall surface extendingto, or optionally forming at least a portion of, the fluid reservoir.Each of the first and second openings may be sealed from exposure to theambient atmosphere with a frangible seal.

In another aspect, the disclosure provides a cartridge rack for use inan automated process. The cartridge rack includes a chassis having a topsurface and a first and a second opposing end, the chassis beingconfigured for releasable attachment to one or more multi-well trays(s)as set forth herein, a plurality of machine readable indicia includingdata disposed on the chassis, and a handle disposed on the first endsurface of the chassis. The chassis is configured for releasableattachment to a plurality (e.g., two or more, or up to five) multi-welltrays. In various embodiments, the chassis is configured for releasableattachment to a cartridge with communicating wells. As discussed above,the cartridge includes a casing having a top surface; a fluid chamberdisposed within the casing, and wherein a first opening is provided inthe top surface of the casing having at least one side wall surfaceextending to, or optionally forming at least a portion of, the fluidchamber; and a fluid reservoir disposed within the casing adjacent toand in fluid communication with the fluid chamber. The machine readableindicia may include identifying information regarding the multi-welltray attached thereto, and may be in the form of a barcode, 2D barcode,QR code, or an RFID. The machine readable indicia may be readablethrough a direct contact connection, a wired connection, or wirelessly.

In another aspect, the disclosure provides a system for conducting anautomated reagent-based assay. The system includes a multi-well tray, acartridge with communicating wells, and an automated pipettor positionedon a robot arm. The multi-well tray may include a plurality of wells,each of the wells containing a lyophilized reagent, wherein theplurality of wells are disposed in alignment with each other and sealedwith a frangible seal, wherein the lyophilized reagent includes atarget-specific reagent. The cartridge with communicating wells includesa casing having a top surface; a fluid chamber disposed within thecasing, and wherein a first opening is provided in the top surface ofthe casing having at least one side wall surface extending to, oroptionally forming at least a portion of, the fluid chamber; a fluidreservoir disposed within the casing in fluid communication with thefluid chamber; and a diluent contained within the fluid chamber. Theautomated pipettor is adapted to execute a retrieval and dispenseprotocol that includes a retrieval of a portion of the reagent from thecartridge and a dispense of the portion of the reagent in one of theplurality of wells, and wherein the retrieval and dispense protocol isrepeated for each of the plurality of wells. In various embodiments, themulti-well tray, the cartridge with communicating wells, and theautomated pipettor are contained within a housing, such as an automatedbiochemical analyzer.

In another aspect, the disclosure provides a method for providing astabilized reagent for a molecular assay. The method includesintroducing a fluid molecular assay reagent to a well, the wellincluding a tapered opening and a capillary insert having a capillarychannel, wherein the tapered opening and capillary channel are in fluidcommunication. Thereafter, subjecting the well containing the reagent toconditions suitable for lyophilizing the fluid molecular assay reagentto prepare a lyophilized reagent. Thereafter, reconstituting thelyophilized reagent by introducing a reconstitution solution to thetapered opening of the well to prepare a reconstituted reagent. Thenwithdrawing the reconstituted reagent using a fluid transfer device thatis introduced into the tapered opening of the well. In variousembodiments, the fluid transfer device is a pipettor. The molecularassay may be a polymerase chain reaction (PCR) assay.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1D are pictorial diagrams showing a receptacle of the presentdisclosure. FIG. 1A is a side view of the receptacle. FIG. 1B is across-sectional view of the receptacle taken along the line 1B-1B inFIG. 1A. FIG. 1C top view of the receptacle. FIG. 1D is a perspectiveview of the receptacle.

FIGS. 2A-2F are pictorial diagrams showing a cap of the presentdisclosure. FIG. 2A is a side view of the cap. FIG. 2B is across-sectional view of the cap taken along the line 2B-2B in FIG. 2A.FIG. 2C top view of the cap. FIG. 2D is a bottom view of the cap. FIGS.2E and 2F are top and bottom perspective views of the cap.

FIG. 3A is an exploded perspective view of the receptacle, the cap, anda portion of a receptacle transport mechanism configured to be insertedinto the cap.

FIG. 3B is a side cross-sectional view of the cap installed in thereceptacle.

FIG. 4A is a perspective view of a multi-well tray for use in anautomated reagent-based analyzer.

FIG. 4B is a perspective view of the multi-well tray with a card insertexploded from the multi-well tray.

FIGS. 5A-5E are pictorial diagrams showing details of a card insert.FIGS. 5B-5E show various views of inner surfaces of the wells of thecard insert.

FIGS. 6A and 6B are pictorial diagrams showing attachment of the cardinsert to the base of the multi-well tray.

FIGS. 7A and 7B are cross-sectional views showing a cap and receptaclecontained within the wells of the multi-well tray.

FIG. 8 is a pictorial diagram showing a cross-sectional view of anautomated pipettor reconstituting a lyophilized reagent contained in awell of a multi-well tray.

FIGS. 9A-9E are pictorial diagrams showing alternative configurations ofa multi-well tray and various exemplary embodiments of inner surfaces ofthe wells therein.

FIGS. 10A and 10B are pictorial diagrams showing perspective views oftwo cartridges with communicating wells.

FIGS. 11A-11D are pictorial diagrams showing a cartridge rack.

DETAILED DESCRIPTION

The present disclosure relates to a system, apparatus, and method forautomated processing of a sample receptacle holder that is adapted foruse in an automated instrument capable of performing nucleic acid-basedamplification assays. Also provided are methods for conductingautomated, random-access temperature cycling processes using the same.

Before the present systems, methods, and apparatuses are described, itis to be understood that this disclosure is not limited to particularmethods and experimental conditions described, as such methods andconditions may vary. It is also to be understood that the terminologyused herein is for purposes of describing particular embodiments only,and is not intended to be limiting, since the scope of the presentdisclosure will be limited only in the appended claims.

As used in this specification and the appended claims, the singularforms “a,” “an,” and “the” include plural references unless the contextclearly dictates otherwise. Thus, for example, references to “themethod” includes one or more methods, and/or steps of the type describedherein which will become apparent to those persons skilled in the artupon reading this disclosure and so forth.

The term “comprising,” which is used interchangeably with “including,”“containing,” “having,” or “characterized by,” is inclusive oropen-ended language and does not exclude additional, unrecited elementsor method steps. The phrase “consisting of” excludes any element, step,or ingredient not specified in the claim. The phrase “consistingessentially of” limits the scope of a claim to the specified materialsor steps and those that do not materially affect the basic and novelcharacteristics of the disclosed subject matter. The present disclosurecontemplates exemplary embodiments of an apparatus and methods of usethereof corresponding to the scope of each of these phrases. Thus, anapparatus or method comprising recited elements or steps contemplatesparticular embodiments in which the apparatus or method consistsessentially of or consists of those elements or steps.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this disclosure belongs. Although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing disclosed herein, the preferred methods andmaterials are now described.

As used herein, a “reaction mixture” refers to a volume of fluidcomprising one or more of a target-specific reagent, diluent forreconstituting a lyophilized reagent, one or more nucleotides, anenzyme, and a sample containing or suspected of containing a nucleicacid.

As used herein, a “sample” or a “test sample” refers to any substancesuspected of containing a target organism or biological molecule, suchas nucleic acid. The substance may be, for example, an unprocessedclinical specimen, a buffered medium containing the specimen, a mediumcontaining the specimen and lytic agents for releasing nucleic acidbelonging to the target organism, or a medium containing nucleic acidderived from a target organism which has been isolated and/or purifiedin a reaction receptacle or on a reaction material or device. In someinstances, a sample or test sample may comprise a product of abiological specimen, such as an amplified nucleic acid to be detected.

As used herein, the term “biochemical assay” refers to a scientificinvestigative procedure for qualitatively assessing or quantitativelymeasuring the presence or amount or the functional activity of a targetentity, such as, but not limited to, a biochemical substance, a cell,organic sample, or target nucleic acid sequence. Included in the term“biochemical assay” are nucleic acid amplification and heat denaturation(i.e., melting). Nucleic acid melting typically involves precise warmingof a double stranded nucleic acid molecule to a temperature at which thetwo strands separate or “melt” apart. The melting process typicallyoccurs at a temperature of about 50° C. to about 95° C.

As used herein, the term “lyophilization” refers to a dehydrationprocess that is typically used to preserve a perishable material and/orfacilitate transport thereof. Thus, “conditions for lyophilization”refer to subjecting a liquid material and/or a vessel containing theliquid material to freezing conditions while reducing the surroundingpressure to allow the frozen water within the material to sublimatedirectly from the solid phase to the gas phase. Such freezing conditionsmay include cooling the material below the lowest temperature at whichthe solid and liquid phases thereof can coexist (known in the art as the“triple point”). Usually, the freezing temperatures are between −50° C.and −80° C., however, one of skill in the art can determine theappropriate freezing temperature to lyophilize the reagent for use inthe automated biochemical assay.

As used herein, the term “reconstituting” refers to the act of returninga lyophilized material to its liquid form. Thus, the term encompassescontacting a fluid, e.g., water or other suitable diluent, with alyophilized reagent for sufficient time to allow the lyophilized reagentto absorb water, thereby forming a stabilized liquid reagent.

Receptacle & Cap

Accordingly, in an exemplary aspect, there is provided a receptacle 100to receive and store fluid test samples for subsequent analysis,including analysis with nucleic acid-based assays or immunoassaysdiagnostic for a particular pathogenic organism. As shown in FIGS.1A-1D, the receptacle 100 is a single-piece receptacle that includes abody 105 having a generally cylindrical upper portion 110 and a taperedlower portion 120. Formed on an outer surface of the body 105 is alaterally-extending flange, which, in the illustrated embodiment,comprises an annular ring 125, which separates the upper and lowerportions of the body. The upper portion 110 of the body 105 has an openend 145 through which fluid samples are deposited or removed from thereceptacle 100. The tapered lower portion 120 has a closed end 150 thatmay either be flat or rounded to provide optical communication with anoptical system, for example, one or more optical fibers (not shown) of abiochemical analyzer. In various embodiments, the bottom surface of theclosed-ended lower portion may be flat or curved.

The receptacle 100 optionally containing a sample or reaction mixture isconfigured for insertion into a receptacle holder of an automatedbiochemical analyzer (not shown). As used herein, a receptacle that is“configured for insertion” refers to the exterior surface of the body105 of the receptacle 100 being sized and shaped to maximize contactbetween the receptacle and a receptacle well of a receptacle holder. Incertain embodiments, this maximal contact refers to physical contact ofthe receptacle well with at least a portion of the receptacle 100. Alsoin certain embodiments, this maximal contact refers to physical contactof the receptacle well with the tapered lower portion 120 of thereceptacle 100, or at least a portion the tapered lower portion 120 ofthe receptacle 100.

Formed in the inner surface 140 of the upper portion 110 of the body 105is one or more longitudinally oriented grooves 135 to facilitate theventing of air displaced from the interior upon deposit of the testsample or attachment of a cap 200 to the receptacle 100. In variousembodiments, a plurality (i.e., 2, 3, 4, 5, 6, 7, or 8) oflongitudinally oriented grooves may be formed in the inner surface 140of the upper portion 110, and the grooves 135 may be equally spacedapart from one another around the entire circumference of the body 105.

Circumscribing the open end 145 of the upper portion 110 of the body 105is a lip 155 extending radially outward from a central axis thereof. Invarious embodiments, the lip 155 tapers from the outer-most portion ofthe radially-extended lip towards the open end of the body, and isconfigured for securable attachment to a cap 200 (FIGS. 2A-2D).

With reference now to FIGS. 2A-2D, the securable cap 200 includes alower portion 220 having an outer surface for sealing engagement of theinner surface 140 of the upper portion 110 of the receptacle 100 and anupper portion 210. To ensure an essentially leak-proof seal when the cap200 is securely attached to the open end 145 of the upper portion 110 ofthe receptacle 100, the outer surface of the lower portion 220 of thecap 200 is formed with one or more annular ribs 230 for contacting theinner surface 140 of the upper portion 110 thereof. In variousembodiments, the lower portion 220 of the cap 200 is formed with 1, 2,or 3 annular ribs 230 for contacting the inner surface 140 of the upperportion 110 of the receptacle 100.

The upper portion 210 of the cap 200 includes an open end 215 forfrictional attachment to a portion of a receptacle transport mechanism300 (FIG. 3A), such as a tubular probe of a pipettor or pick-and-placerobot. Guiding insertion of the receptacle transport mechanism 300 intothe open end 215 of the upper portion 210 of the cap 200 are one or morelinear ribs 260 formed in the inner surface 270 of the upper portion210. The linear ribs 260 protrude towards an axial center of the cap200, thereby decreasing the inner fitment diameter of the upper portion210 of the cap 200. Each linear rib 260 may be beveled (as at 262) at anupper, or proximal, end thereof. These linear ribs 260 can, among otherthings, enhance the frictional attachment to the receptacle transportmechanism 300. In various embodiments, 1, 2, 3, 4, 5, 6, 7, or 8 linearribs 260 are formed in the inner surface 270 of the cap 200 and extendat least a portion of the way down the length of the upper portion 210thereof.

At least one of the linear ribs 260 may be formed with a portion 265thereof, e.g., at a lower, or distal, end, that gradually tapersradially inward toward a central axis of the upper portion 210 of thecap. In other words, the amount of protrusion of the linear rib 260 maygradually increase in size as the linear rib 260 approaches the bottom245 of the upper portion 210 of the cap 200. Alternatively, or inaddition thereto, in certain embodiments, the linear rib 260 maygradually increase in overall thickness as it approaches the bottom 245of the upper portion 210 of the cap 200. Thus, gradual increase inthickness or radial geometry is contemplated for the gradual tapering ofthe one or more linear ribs 260, which serves to stabilize and centerthe receptacle transport mechanism 300 as it is lowered into the cap 200for transport.

Corresponding with each linear rib 260 and disposed on the exteriorsurface of the upper portion 210 of the cap 200 are one or moreindentations, or recesses, 234 that extend along at least part of thelength thereof. The recesses may be formed in any shape such as, forexample, concave, notched, squared, etc. Thus, at least one recess 234is formed in the exterior surface of the upper portion 210 of the cap200. In various embodiments, the length of the recess 234 is the same asthe length of the corresponding linear rib 260, and each linear rib 260is positioned such that it lies on the inner surface 270 of the cap 200in a location that directly opposes the position of the at least onerecess 234 formed on the outer surface of the cap 200 in a one-to-onerelationship. The coupling of a linear rib 260 with an recess 234 inthis manner enhances the predictability of the frictional attachment ofthe cap 200 to a receptacle transport mechanism 300. In certainembodiments, as the receptacle transport mechanism 300 is lowered intothe open end 215 of the cap 200, it contacts the one or more linear ribs260, thereby pressing against the one or more linear ribs 260. Suchpressing against the linear ribs 260 causes the cap 200, and recesses234 to flex and/or expand radially outward with respect to the axialcenter thereof to accommodate the receptacle transport mechanism 300 andthus enhance frictional attachment of the cap 300 to the receptacletransport mechanism 300. Accordingly, 1, 2, 3, 4, 5, 6, 7, or 8 recesses234 may be formed on the exterior surface of the upper portion 210 ofthe cap 200.

Circumscribing the open end 215 of the upper portion 210 of the cap 200is a lip 225 extending radially outward from a central axis thereof. Invarious embodiments, the lip 225 tapers from the open end 215 towardsthe lower portion 220. Protruding from the taper of the lip 225 are aplurality of protrusions 235. The protrusions 235 may be equally spacedapart from one another and facilitate stacking and/or docking within awell of a multi-well tray 400 (FIG. 4A) for use in an automatedbiochemical analyzer. In various embodiments, 1, 2, 3, 4, 5, 6, 7, or 8protrusions 235 are formed in the taper of the lip 225.

In various embodiments, the cap 200 is removed from the receptacletransport mechanism 300 by means of a sleeve 306 coaxially disposed overa tip of the receptacle transport mechanism 300 and axially movable withrespect to thereto. The sleeve 306 moves axially with respect to the tiptoward a distal end of the tip and contacts the lip 225 of the cap,thereby pushing the cap off the tip of the receptacle transportmechanism 300.

Separating the upper portion 210 from the lower portion 220 of the cap200 is a flange 240 that extends radially away from an axial centerthereof. The flange 240 includes a plurality of locking arms 250 thatextend from the flange 240 toward the lower portion 220 of the cap 200.The locking arms 250 are shaped for securely engaging the lip 155 of thereceptacle 100, and may be disposed to allow for removable attachment ofthe cap 200 to the receptacle 100, while maintaining a leak-proof sealof the contents thereof. In various embodiments, 1, 2, 3, 4, 5, 6, 7, or8 locking arms 250 are formed in the cap 200.

The flange 240 of the cap 200 additionally serves to form a bottom 245to separate the upper portion 210 from the lower portion 220, therebyclosing the interior of the receptacle 100 from the environment.However, in certain embodiments, the bottom 245 is scored 255 forpiercing by a mechanism for collecting and/or adding reagents to thetest sample within the receptacle 100. Such piercing avoids the need toremove the secured cap 200 from engagement with the receptacle 100,while providing access to the contents therein.

The receptacle 100 and cap 200 of the present disclosure may be preparedfrom a number of different polymer and heteropolymer resins, including,but not limited to, polyolefins (e.g., high density polyethylene(“HDPE”), low density polyethylene (“LDPE”), a mixture of HDPE and LDPE,or polypropylene), polystyrene, high impact polystyrene andpolycarbonate. An example of an HDPE is sold under the trade nameAlathon M5370 and is available from Polymerland of Huntsville, N.C.; anexample of an LDPE is sold under the trade name 722 and is availablefrom The Dow Chemical Company of Midland, Mich.; and an example of apolypropylene is sold under the trade name Rexene 13T10ACS279 and isavailable from the Huntsman Corporation of Salt Lake City, Utah.Although LDPE is a softer, more malleable material than HDPE, thesoftness of LDPE provides flexibility in the locking arms 250 of the cap200 to securably engage the lip 155 of the receptacle 100. And, while acap made of HDPE is more rigid than one made of LDPE, this rigiditytends to make an HDPE cap more difficult to penetrate than one made ofLDPE. It should be understood that the receptacle 100 and cap 200 may becomprised of a combination of resins, including, for example, a mixtureof LDPE and HDPE, preferably in a mixture range of about 20% LDPE:80%HDPE to about 50% LDPE:50% HDPE by volume. In addition, the amounts ofLDPE and HDPE used to form each of the receptacle 100 and cap 200 may bethe same or different. In various embodiments, at least a portion of thecap 200 is formed from an opaque material having low to noautofluorescence characteristics. Also, in certain embodiments, theportion of the cap 200 formed from an opaque material having low to noautofluorescence characteristics is at least the lower portion 220thereof, including the inner surface 232 of the lower portion 220 of thecap 200.

Regardless of the type or mixture of resins chosen, the receptacle 100and cap 200 are preferably injection molded as unitary pieces usingprocedures well-known to those skilled in the art of injection molding,including a multi-gate process for facilitating uniform resin flow intothe receptacle and cap cavities used to form the shapes thereof. Uniformresin flow is desirable for achieving consistency in thickness, which isimportant for a variety of reasons, including for the penetrable bottom245 of the cap 200; to ensure a secure, such as an air-tight, engagementof the cap 200 and receptacle 100; to ensure a predictable engagement ofthe cap 200 with the receptacle transport mechanism 300; and to ensuremaximal contact of the receptacle 100 with a receptacle well of areceptacle holder.

Method for Automated Removal of a Cap

In another aspect, disclosed herein is a method for automated removal ofa cap from a capped reaction receptacle. The method includes providing areceptacle 100 securably engaging the lip 155 of a receptacle 100, asshown in FIG. 3B. Thereafter, performing an automated motion ofcontacting an inner portion 280 of at least one of the plurality oflocking arms 250 of the cap 200 with a raised annular ridge definedaround a receptacle slot. The receptacle slot may be provided in areceptacle holder of an automated biochemical analyzer, alternativelythe receptacle slot may be provided in a card or cartridge intended tobe removed from an automated biochemical analyzer. The contacting urgesthe locking arms 250 away from the lip 155 of the receptacle 100,thereby disengaging the cap 200 from the receptacle 100. While the cap200 is being disengaged from the receptacle 100, an automated motion isperformed to lift the cap 200 away from the receptacle 100, therebyremoving the cap 200 from the receptacle 100. In various embodiments,the automated motion is performed by a receptacle transport mechanism300 (FIG. 3A), such as, for example, a pipettor or pick-and-place robot.

Multi-Well Tray

In another aspect, disclosed herein is a multi-well tray for use in anautomated process. Referring now to FIGS. 4A and 4B, a multi-well tray400, as shown, includes a base 410 having disposed in a top surface 417thereof, a plurality of wells 415, 416. A card insert 420 (see also FIG.5A) configured for removable attachment to the base 410, is attachedthereto. When the card insert 420 is attached to the base 410, a topsurface 425 of the card insert 420 is substantially parallel to andflush with the top surface 417 of the base 410.

Disposed in the top surface 425 of the card insert 420, is a pluralityof wells 430, each configured for containing one or more reagents usedfor performing a biochemical analysis. Each well 430 of the card insert420 corresponds to at least one of the wells 415 disposed in the base410. Thus, in certain embodiments, after attachment of the card insert420 to the base 410, the multi-well tray 400 takes on the uniformappearance of, for example, a multi-well plate. The wells 415, 416disposed in the base 410 may be arranged in pairs, where each paircorresponds to a single well 430 of the card insert 420. As such, themulti-well tray 400 may include a plurality of sets 435 of wells, whereeach set 435 includes a first well 415 and a second well 416, which aredisposed in the top surface 417 of the base 410, and a third well 430disposed in the top surface 425 of the card insert 420. The wells ofeach set 435 of wells may be in alignment with each other, therebyresulting in a multi-well tray 400 that is spatially indexed such thanan automated receptacle transport mechanism 300 can accurately identifyand/or access any of the plurality of wells when the multi-well tray 400is placed or inserted into an automated system. In certain embodiments,the multi-well tray 400 includes ten sets 435 of wells. As such, thebase 410 is formed with ten pairs of first and second wells 415, 416 andthe card insert 420 is formed with ten third wells 430, where each ofthe first, second, and third wells of the set 435 are arranged inalignment with each other. Thus, the multi-well tray 400 may include tenreceptacles 100 and ten caps 200 provided therein for used in anautomated biochemical analyzer.

The first and second wells 415, 416 of the set 435 are configured toreceive a cap 200 and a receptacle 100, respectively. While it should beunderstood that the terms “first” and “second” as used to distinguishthe wells formed in the base 410, for descriptive purposes, the “firstwell”, or cap well, 415 will refer to a well configured to receive areceptacle cap 200.

With reference now to FIGS. 7A and 7B, the first well 415 of the base410 is defined by a cylindrical wall 470 and a bottom wall 472. Formedin the center of the bottom surface 472 is a protrusion 475 extendingupwardly toward the top surface 417 of the base 410. The protrusion 475is sized and shaped for engagement, optionally frictional engagement,with a hollow portion 232 of the lower portion 220 of the cap 200.Alternatively, or in addition thereto, the cylindrical wall 470 may beformed with a plurality of tabs 477 protruding towards the axial centerof the first well 415. Such tabs 477 are configured for securelyengaging at least a portion of the cap 200 to prevent the cap 200 fromdislodging from the multi-well tray if, for example, the multi-well trayis inverted or shaken. In certain embodiments, 2, 3, 4, 5, 6, 7, or 8tabs 477 are formed in the cylindrical wall 470 of the first well. Eachof tabs 477 may securely engage the top surface of the flange 240 of thecap 200.

Similarly, the “second well”, or receptacle well, 416 will refer to awell configured to receive a receptacle 100. As shown in FIGS. 7A and7B, the second well 416 is defined by a cylindrical wall 480 and abottom wall 482. Formed in the center of the bottom wall 482 is athrough-hole 485base. The through-hole 485 is sized and shaped inconformance with the outer surface of the lower portion 120 of thereceptacle 100. As such, the through-hole may be tapered at an anglecorresponding to the angle of the lower portion 120. As shown in FIG.7A, the bottom wall 482 of the second well 416 forms an annular ledge atthe perimeter of the through-hole for engaging the ring 125 of thereceptacle 100. Alternatively, or in addition thereto, the cylindricalwall 480 may be formed with a plurality of legs 487 protruding towardsthe axial center of the second well 416. Such legs 487 are configuredfor securely engaging at least a portion of the receptacle 100 toprevent the receptacle 100 from dislodging from the multi-well tray if,for example, the multi-well tray is inverted or shaken. In certainembodiments, 2, 3, 4, 5, 6, 7, or 8 legs 487 are formed in thecylindrical wall 480 of the second well 416. Each of the legs 487 maysecurely engage the top surface of the ring 125 of the receptacle 100.

As discussed above, the third well, or reagent well, 430 of each set 435contains one or more reagents for performing a biochemical analysis. Incertain embodiments, the third well 430 of the set 435 contains alyophilized reagent 495 (FIGS. 8 and 9C), and may be sealed with afrangible seal 440 (FIG. 8). For example, each well 430 of the cardinsert 420 may be sealed with a metallic foil (or foil laminate) using,for example, a pressure sensitive adhesive which is applied to the topsurface 425 thereof. The frangible seal 440 may further include aplastic liner, such as a thin veneer of HDPE applied to one or bothsurfaces thereof, which promotes attachment of the frangible seal 440 tothe top surface 425 when a heat sealer is used. Heat sealing is awell-known process and involves the generation of heat and theapplication of pressure to the surface being sealed, which, in thiscase, is the top surface 425 or a raised lip 427 (see FIGS. 4A, 5A)surrounding the well 430 of the card insert 420. Alternatively, anyknown ultrasonic welding procedure using either high frequency or highamplitude sound waves may also be used to affix the frangible seal 440to the card insert 420. The card insert 420 may include a plurality offrangible seals 440, each of which sealing a single well 430, or mayinclude a single sheet that seals all wells 430 disposed therein.

A single lyophilized reagent 495 may be provided in each well 430 of thecard insert 420. However, in certain embodiments, one or more wells 430of the card insert 420 may contain a different lyophilized reagent 495,such as a different target-specific reagent. Thus, each well 430 of thecard insert 420 may contain a distinct lyophilized reagent 495 comparedwith the lyophilized reagent 495 contained in at least one other of theplurality of wells 430 therein. In various embodiments, the card insert420 does not contain non-reagent consumables. As used herein, a“reagent” refers to a substance or mixture for use in a chemical orbiochemical reaction. Thus, a “non-reagent consumable” refers to acomponent that is used by an automated biochemical assay, but is not areagent. Exemplary non-reagent consumables include, but are not limitedto, contamination limiting elements, receptacles 100, and caps 200.

Referring now to FIGS. 5A-5E, each well 430 of the card insert 420 isdefined by a side wall, or well wall, 450 and a bottom, or bottom wallor bottom wall portion, 455. In various embodiments, the side wall 450tapers from an upper end thereof to the bottom 455, and may therefore bereferred to as a conical wall. As shown in FIGS. 5B-5E, the bottom 455of each well may be formed with one or more features to facilitatedeposit of and collection of fluid from the well. Such features include,but are not limited to a concave groove 457, 460 (FIGS. 5C, 5D, 5E),convex ridge (not shown), or a set of grooves positioned in a crisscrosspattern (not shown). The features may be located at the axial center ofthe well 430, as shown in FIG. 5C, or may be off-set to a side thereof,as shown in FIG. 5B. Alternatively, or in addition thereto, the sidewall 450 may be formed with a plurality of bumps 462 on the surfacethereof for additional facilitation of depositing and/or collectingfluids contained therein. The side wall 450 of each well 430 of the cardinsert 420 may further be formed with a plurality of rigid guides 465that protrude radially from the side wall 450 towards the axial centerof the well 430. Such rigid guides 465 guide a pipette tip 310 (FIGS. 8and 9C) mounted on an automated pipettor toward the axial center of thewell 430 as the tip is lowered therein, and may further serve to retainthe lyophilized reagent at, or adjacent to, the bottom 455 of the well430. In various embodiments, each well 430 may be independently formedwith 2, 3, 4, 5, 6, 7, or 8 rigid guides 465 protruding from therespective tapered side wall 450.

The features formed at the bottom 455 of the well 430, such as grooves,ridges, and/or bumps, interfere with the end of a pipette tip insertedinto the well 430 and thus prevent the end of the pipette tip frommaking sealing contact with the bottom 455 so as to prevent a negativepressure build up within the pipette tip during a fluid aspiration. Forexample, as shown in FIG. 5E, a feature formed on the bottom 455 of well430, such as groove 457, provides a clearance that prevents a pipettetip 310 from making sealing contact with the bottom 455 of the well 430.

Additionally, in certain embodiments, the side wall 450 of each well 430of the card insert 420 may include one or more retention features (FIGS.8, and 9C-9D) that can be used to retain the lyophilized reagent 495 at,or adjacent to, the bottom 455 of the well 430 when, for example adiluent is deposited into the well 430 for reconstitution of alyophilized reagent. In FIGS. 9C and 9D, the retention features areshown within a well 715 of an alternative embodiment of a multi-welltray 700 described below. In various embodiments, the retention featuremay include one or more protrusions or an annular ridge 800 formed abovethe area to be occupied by the lyophilized reagent 495, and extendingtoward the axial center of the well 430. Such protrusions or annularridge 800 narrow the opening of the side wall 450 such that the openingis smaller than the diameter of the lyophilized reagent 495.

As shown in FIG. 9E, the annular ridge 800 may be formed by insertingone or more heat stakes 880 into the wells 430, such that the side wall450 is deformed, thereby forming an annular ridge 800 therein. The oneor more heat stakes 880 may be attached to an apparatus 890, which mayheat the one or more heat stakes 880, thereby providing sufficient heatto deform the side wall 450 at a point along the taper where thediameter thereof equals that of the diameter of the heat stake.

In various embodiments, the retention feature may also take the form ofone or more solid extensions 810 formed over the area to be occupied bythe lyophilized reagent 495. Such extensions 810 connect opposing areasof the side wall 450, thereby retaining the lyophilized reagent 495 at,or adjacent to, the bottom 455 of the well 430. In various embodiments,the side wall 450 may be formed to mimic the thread of a coarse screw asshown at 820. Such a threaded feature 820 may be formed during injectionmolding of the well 430, or may be formed by applying a heated screwportion to the well wall, thereby forming a spiral channel along alength thereof, through which fluid may run to the bottom 455 usinggravitational force. In various embodiments, the retention feature maybe provided in the form of a tapered ring insert 830 that is fixedlyattached to the side wall 450 either before or after deposit of thelyophilized reagent 495. The tapered ring 830 may be formed of plasticand include an exterior surface that tapers in accordance with the taperof the side wall 450. When present, the tapered ring 830 narrows theopening of the well 430 such that the lyophilized reagent 495 isretained at, or adjacent to, the bottom 455 of the well 430.

Whether the lyophilized bead 495 is formed within the well from aninitially liquid reagent or the solid bead is formed outside the welland then placed into the well may depend on whether the retentionfeature is an integral part of the well. If the retention feature is anintegral part of the well, a solid bead could not be placed into thewell below the retention feature and a liquid reagent must be dispensedinto the bottom of the well and then lyophilized If the retentionfeature is not an integral part of the well, a lyophilized bead could beplaced into the well, and then the retention feature installed in thewell over the lyophilized bead.

As shown in FIG. 9D, the inner surface of a well wall may besubstantially vertical as at 840, while an exterior surface of the wellretains its tapered shape. In certain embodiments, the inner surface ofthe well wall may be substantially vertical as at 840, while theexterior surface of the well is also substantially vertical (not shown).When present, the vertical wall 840 allows the entirety of a liquidreagent to be lyophilized to settle at the bottom 455 of the well,thereby ensuring reagent uniformity upon lyophilization.

In various embodiments, as also shown in FIG. 9D, the retention featuremay be in the form of a capillary insert 850 that is fixedly attached tothe well wall. The capillary insert 850 may be formed of plastic andinclude an exterior surface that tapers in accordance with the taper ofthe well wall. In an exemplary embodiment, the well and capillary insert850 may be formed as a single unit. The capillary insert 850 may notextend completely to the bottom of the well, thereby defining a chamber856 below a bottom end of the capillary insert 850. The inner surface ofthe capillary insert 850 may include substantially vertical wallsforming a capillary channel 852 extending from an upper end of theinsert to a lower end of the insert through which fluid will flow viacapillary attraction, and within which the fluid will be retained as aresult of the combination of surface tension and adhesive forces betweenthe fluid and the walls of the capillary channel. The capillary insert850 may further include an open upper end 854 that tapers from a topsurface of the insert 850 to the channel 852. Thus, when a capillaryinsert 850 is present in a well and a liquid reagent to be lyophilizedis deposit therein, the reagent remains held within the capillarychannel thereof, and is prevented from flowing into the bottom of thewell. After lyophilizing the liquid reagent, the lyophilized reagent 495remains lodged within the channel 852 of the capillary insert 850.Deposit of a diluent for reconstitution of the lyophilized reagent 495is accomplished by addition of the diluent to the tapered open upper end854 of the capillary insert 850. The diluent then flows within thecapillary channel 852 via capillary attraction, and is retained thereinas a result of the combination of surface tension and adhesive forcesbetween the diluent and the walls of the capillary channel 852. Oncereconstituted, the reagent may be collected by insertion of the pipettetip 310 into the tapered open upper end 854 of the capillary insert 850and withdrawing the liquid reagent therefrom. The entirety of the liquidreagent may therefore be collected at the tapered open upper end 854 ofthe capillary insert 850 since the liquid will travel upwards due tocapillary attraction within the channel 852 of the capillary insert 850.

Alternatively, or in addition thereto, the bottom 455 of the well can beformed to include a roughened surface, thereby providing sufficientsurface area to which the lyophilized reagent 495 will adhere uponformation thereof. Alternatively, or in addition thereto, thelyophilized reagent 495 will adhere to, or adjacent to, the bottom 455of the well 430 through a static electrical attractive force created onthe well wall 450 and/or bottom 455 of the well 430. In suchembodiments, the inner surface of the well 430 is provided with anelectrical charge such that the lyophilized reagent 495 adheres thereto.

In various embodiments, the retention feature may take the form of aninsert through which the pipette tip 310 may be inserted. For example,as shown in FIG. 9D the retention feature may be a fingered collar 860that is fixedly attached to a top portion of the well. The fingeredcollar 860 may be formed of plastic and include an exterior surface thattapers in accordance with the taper of the well wall. The fingeredcollar 860 may include one or more (i.e., 1, 2, 3, 4, 5, 6, 7, or 8)fingers extending from a bottom surface thereof, and protruding along aradius of curvature toward the axial center of the well. The one or morefingers may be flexible such that contact with a pipette tip 310inserted therein causes the fingers to flex toward the well wall,thereby allowing the pipette tip 310 to pass there through. Uponwithdrawal of the pipette tip 310, the fingers return to a rest positionsuch that the fingers protrude along the radius of curvature toward theaxial center of the well.

In an alternative embodiment, the retention feature may take the form ofa collar 870 that resembles the fingered collar 860, but does notinclude the one or more fingers protruding therefrom. Such a collar 870may be fixedly attached to a top or center portion of the well wall, andmay be formed of plastic and include an exterior surface that tapers inconformance with the taper of the well wall. When present, the collar870 narrows the well wall to retain the lyophilized reagent 495 at, oradjacent to, the bottom 455 of the well, while allowing the pipette tip310 to pass there through.

Each of the base 410 and card insert 420 may be independentlyconstructed of an injection molded plastic, such as the plasticsdescribed above. The plastic used to form the base 410 may be the sameor different from the plastic used to form the card insert 420. Forexample, the card insert 420 may be formed from a plastic having lowerpermeability to air and/or moisture than the plastic forming the base410. Such plastics may be more expensive than their conventionalcounterparts but, due to the decreased air and moisture permeability,provide for enhanced stability of reagents, such as lyophilized reagentscontained in the wells thereof. Any exterior surface of the base 410 orcard insert 420 may further include one or more identifying labels 490,such as a barcode, 2D barcode, quick response (QR) code, radio frequencyidentification (RFID), or other human or machine readable indicia,disposed thereon. The information carried on such label may includeidentifying information regarding the multi-well tray 400 and/or cardinsert 420, including information regarding the reagents containedtherein, such as lot number, serial number, assay type, expiration date,etc. In various embodiments, the base 410 may include one or morebarcodes and/or QR codes on a side surface thereof for identifyingassays to be performed by the automated biochemical analyzer.

As shown in FIG. 4B, the base 410 may be formed with one or more lockingarms 445 positioned for locking engagement with the card insert 420.Additionally, the card insert 420 may be formed with one or morecorresponding lock-holes 447 for receiving the locking arms 445 of thebase 410. Once secured into the base 410 by the locking arms 445 and/orthe lock-holes 447, the card insert 420 is prevented from detachmenttherefrom. However, in certain embodiments, locking arms 445 may bemoved out of locking engagement with the card insert 420 to release thecard insert 420 from the base 410. Such releasable engagement providesfor reuse of the base 410, if necessary, and/or replacement of a cardinsert 420 should the need arise.

As shown in FIG. 6A, base 410 may be further formed with one or morelocking fingers 422 disposed on a side surface thereof. The lockingfingers 422 are configured for releasably engaging a rack to secure thebase 410 to the rack for use in automated processing. In variousembodiments, the base 410 may further include a release 437 for urgingthe locking fingers 422 away from the engaging surface of the rack tofacilitate removal therefrom.

As shown in FIG. 6B, the card insert 420 may be secured to the base 410by means of locking features 424 disposed along opposed sides of thecard insert 420 that are configured for locking engagement withcooperating ledges 412 formed in the base 410

FIGS. 9A-9E show an alternative embodiment of a multi-well tray 700.Referring now to FIGS. 9A and 9B, the multi-well tray 700 includes abase 710 having disposed in a top surface 717 thereof, a plurality ofwells 715. The base 710 also includes an arm 720 for engagement by atransport mechanism, such as a rotary distributor (not shown) fortransport within an automated biochemical analyzer. As shown in FIG. 9B,the bottom surface 730 of the base 710 is formed with one or more snapfingers 735, which define a slot 740 into which an element (not shown)of the biochemical analyzer is inserted. Thus, snap fingers 735 graspthe element (not shown) of the biochemical analyzer, thereby forming asecure attachment thereto.

In this alternative embodiment, all of the wells 715 are configured tocontain one or more reagents used for performing automated biochemicalanalysis. Similar to the wells 430 of the multi-well tray insert 420,each well 715 is defined by an inner side wall 750 and a bottom 755. Invarious embodiments, the side wall 750 tapers from a top portion of thewell 715 to the bottom 755, as shown in FIG. 9C.

As discussed above, the bottom 755 of each well 715 may be formed withone or more features to facilitate deposit of and collection of fluidfrom the well. Such features include, but not limited to a concavegroove 457, 460 (FIGS. 5B-5D), a convex ridge (not shown), or a set ofgrooves positioned in a crisscross pattern (not shown). The features maybe located at the axial center of the well 715, as shown in FIG. 5C, ormay be off-set to a side thereof, as shown in FIG. 5B. Alternatively, orin addition thereto, the inner wall 750 may be formed with a pluralityof bumps 462 (FIGS. 5B-5D) on the surface thereof for additionalfacilitation of depositing and/or collecting fluids contained therein.The inner wall 750 of each well 715 of the card 700 may further beformed with a plurality of rigid guides 465 (FIG. 5B) that protruderadially from the inner wall 750 towards the axial center of the well715. Such rigid guides 465 guide the tip 310 (FIGS. 8 and 9C) mounted onan automated pipettor toward the axial center of the well 715 as the tipis lowered therein, and may further serve to retain the lyophilizedreagent 495 at, or adjacent to, the bottom 755 of the well 715. Invarious embodiments, each well 715 may be independently formed with 2,3, 4, 5, 6, 7, or 8 rigid guides protruding from the respective taperedwell wall 750.

Additionally, in certain embodiments, the inner well walls 750 of eachwell 715 of the card 700 may include one or more retention features 800,810, 820, 830, 840, 850, 860, 870 (FIGS. 8 and 9C-9D), as describedabove, configured to retain the lyophilized reagent 495 at, or adjacentto, the bottom 755 of the well 715 when, for example a diluent isdeposited into the well 715 for reconstitution. In various embodiments,the retention features may include an annular ridge 800 formed above thearea to be occupied by the lyophilized reagent 495, and extending towardthe axial center of the well 715. In various embodiments, the retentionfeatures may also take the form of one or more solid extensions 810formed over the area to be occupied by the lyophilized reagent 495. Suchextensions 810 connect opposing areas of the well wall 750, therebyretaining the lyophilized reagent 495 at, or adjacent to, the bottom 755of the well 715. In various embodiments, the well 715 may include any ofthe various inserts 830, 850, 860, or 870, as discussed above.Alternatively, or in addition thereto, the well wall 750 may be avertical wall 840 or may be formed to include a screw thread (i.e., aspiral channel) 820. Alternatively, or in addition thereto, the bottom755 of the well can be formed to include a rough surface, therebyproviding sufficient surface area to which the lyophilized reagent 495will adhere upon formation thereof. Alternatively, or in additionthereto, the lyophilized reagent 495 will adhere to the bottom 755 ofthe well 715 through a static electrical attractive force created on thewell wall 750 and/or bottom 755 of the well 715.

Cartridge With Communicating Wells

In another aspect of the disclosure, a cartridge 500 with communicatingwells for use in an automated process is shown in FIGS. 10A and 10B,which depict different alternative cartridge embodiments. The cartridge500 includes a casing 510 having a top surface 517, a fluid chamber 520,and a fluid reservoir 515. In various embodiment, the fluid chamber 520and the fluid reservoir 515 comprise wells open at the top surface 517.In various embodiments, as reflected in the drawings, the fluid chamber520 has a smaller volumetric capacity than the fluid reservoir 515. Asfurther reflected in the drawings, the perimeter of the open end of thefluid chamber 520 may be smaller than the perimeter of the open end ofthe fluid reservoir 515, and thus the exposed surface of a fluid in thefluid chamber 520 would be smaller than the exposed surface of a fluidin the fluid reservoir 515.

The fluid chamber 520 and the fluid reservoir 515 may contain the sameliquid, such as a diluent or a reconstitution solution forreconstituting the lyophilized reagent (e.g., lyophilized reagent 495).

The cartridge 500 may be provided with one or more fluid connectionsbetween the fluid chamber 520 and the fluid reservoir 515. Thus, invarious embodiments, one or more openings 525 and/or 527 between thefluid chamber 520 and the fluid reservoir 515 may include one or morechannels between the fluid reservoir 515 and the fluid chamber 520 toprovide a path through which a liquid or gas may flow between the fluidchamber 520 and the fluid reservoir 515. An opening, such as opening527, between the fluid chamber 520 and the fluid reservoir 515 may beprovided by a slot or hole formed in a wall separating the fluid chamber520 and the fluid reservoir 515.

In various embodiments, a first opening 525 is provided proximate alower portion of the fluid chamber 520 and the fluid reservoir 515(e.g., at a base of the casing 510) for fluid communication between thefluid chamber 520 and the fluid reservoir 515, and a second opening 527is provided proximate an upper end (i.e., near the open ends) of thefluid chamber 520 and the fluid reservoir 515 for fluid communicationbetween the fluid chamber 520 and the fluid reservoir 515.

As shown in FIG. 10A, the cartridge 500 may also include a second fluidreservoir 530 disposed within the casing and adjacent to the fluidchamber 520. The second reservoir 530 can be utilized to store the sameor a different liquid than is stored in reservoir 515. In certainembodiments the second reservoir 530 is not in fluid communication withthe fluid reservoir 515 or the fluid chamber 520. In certain embodimentsthe fluid reservoir 515 and the fluid chamber 520 contain areconstitution solution, and the second reservoir 530 contains oil.

In various embodiments, each of the fluid chamber 520, fluid reservoir515, and second reservoir 530 may be sealed with a seal (not shown),such as a metallic foil (or foil laminate). A seal over the fluidreservoir 515, the fluid chamber 520, and/or the second reservoir 530may be provided to prevent spillage of fluid contents in case cartridge500 is tipped, dropped, shaken, or inverted, The seal also prevents orretards evaporation of the fluid contents of the sealed reservoir orchamber by preventing or limiting exposure to ambient atmosphere. Theseal may further include a plastic liner, such as a thin veneer of HDPEapplied to one or both surfaces thereof. The seal may be secured using,for example, a pressure sensitive adhesive or heat seal securing thefoil to the top surface 517 securing the seal about the perimeter of theopening of each reservoir or chamber. A plastic liner, such as a thinveneer of HDPE applied to one or both surfaces of the seal, promotesattachment of the frangible seal to the top surface 517 when a heatsealer is used. The one or more openings (525, 527) may also be sealedwith a frangible seal to prevent exposure to the ambient atmosphere

The fluid reservoir 515 and the fluid chamber 520 and any connectingopening(s) are configured so that as fluid is removed from the fluidchamber 520, replacement fluid flows into the fluid chamber 520 from thefluid reservoir 515 (e.g., through an opening 525 provided proximate alower portion of the fluid chamber 520 and fluid reservoir 515).Moreover, if the fluid reservoir is sealed, one or more conduits may beprovided to permit air to flow into the fluid reservoir 515 (e.g.,through an opening 527 provided proximate an upper portion of the fluidchamber 520 and fluid reservoir 515) as fluid is drawn out of the fluidreservoir 515 to thereby allow the pressure in the reservoir toequilibrate.

The chamber 520 is may be sealed with a frangible seal that ispuncturable by a pipette tip. The entire volume of fluid in the fluidchamber 520 and the fluid reservoir 515 is accessible to a fluidtransfer apparatus, but a relatively small surface area of thatfluid—e.g., corresponding to the width of the chamber 520 or to the sizeof a puncture hole formed in a seal over the chamber 520—is exposed toair. Thus, the configuration of the cartridge 500 retards evaporation offluids contained therein.

An amount of liquid, such as reconstitution solution, may be removedfrom the fluid chamber 520 within an automated pipettor and transferredto a well (e.g., well 430 or 715) to reconstitute a lyophilized reagent(e.g., lyophilized reagent 495), as described below.

The cartridge 500 may be constructed of an injection molded plastic,such as the plastics described above. As discussed above, the plasticused to form the cartridge 500 may be one having low permeability to airand/or moisture.

Any exterior surface of the cartridge 500 may further include one ormore identifying labels, such as a barcode, 2D barcode, quick response(QR) code, radio frequency identification (RFID), or other human ormachine readable indicia, disposed thereon. The information carried onsuch label may include identifying information regarding the cartridge500, including information regarding the liquids/reagents containedtherein, such as lot number, serial number, assay type, expiration date,etc.

Cartridge Rack

In another aspect, disclosed herein is a cartridge rack for use in anautomated process. With reference now to FIGS. 11A-11D, the cartridgerack 600 includes a chassis 610 and a handle 620. A top surface 615 ofthe chassis 610 is configured for releasable attachment of one or moremulti-well trays 400 thereto, and therefore may include a plurality oflocking members 625 for releasably engaging the locking fingers 422 ofthe multi-well tray 400 (see FIG. 6A). While the FIG. 11B shows that twolocking members 625 are provided for each multi-well tray 400, it shouldbe understood that the number of locking members 625 provided for eachmulti-well tray 400 will correspond with the number of locking fingers422 provided on the multi-well tray 400 to be attached thereto.

Disposed on a surface of the chassis 610 is a plurality of identifyinglabels such as machine readable indicia 630, such as a barcode, 2Dbarcode, quick response (QR) code, radio frequency identification(RFID), or other human or machine readable indicia, disposed thereon.The information carried on such label may include identifyinginformation regarding the cartridge rack 600, multi-well tray(s) 400attached thereto, and/or the card insert(s) 420 attached to themulti-well tray(s) 400, and/or the multi-well tray 400 position on therack. The machine readable indicia 630 may be readable through a directcontact connection, a wired connection, or a wireless connection betweenthe cartridge rack 600 on the automated biochemical analyzer.

In various embodiments, the chassis 610 is configured for releasableattachment of two or more multi-well trays 400 thereto, and may furtherbe configured for releasable attachment to a cartridge withcommunicating wells 500. Thus, in an exemplary embodiment, fivemulti-well receptacles 400 and one cartridge 500 may be releasablyattached to the chassis 610 for use in an automated biochemicalanalyzer. However, 2, 3, 4, 5, 6, 7, or 8 multi-well trays 400, and/or1, 2, 3, or 4 cartridges 500 may be attached to the chassis 610.

System for Automated Reagent-Based Assay

In another aspect, the present disclosure provides a system for anautomated reagent-based assay. The system includes a multi-well tray 400that includes a plurality of wells 430, a cartridge with communicatingwells 500, and an automated pipettor positioned on a robot arm (notshown). The system includes a housing within which each of thecomponents are located. Each well 430 of the multi-well tray 400 shownand discussed above contains a lyophilized reagent 495 and is arrangedin alignment with each other. The wells 430 of the multi-well tray 400may be sealed with a frangible seal. The multi-well tray 400 may furtherinclude a plurality of additional wells 415, 416 provided for receivinga receptacle 100 and a cap 200. When present, the additional wells arepositioned in aligned pairs, and the pairs are positioned in alignmentwith at least one well 430 containing a reagent, such as a lyophilizedreagent 495. Thus, the multi-well tray 400 may contain a plurality ofsets 435 of wells, where a first well 415 contains a cap 200, a secondwell 416 contains a receptacle 100, and a third well contains a reagentsuch as a lyophilized reagent 495.

The cartridge with communicating wells 500 includes a casing 510 havinga top surface 517, a fluid chamber 520. A first opening 527 is providedin the top surface of the casing having at least one side wall surfaceextending to, or optionally forming at least a portion of, the fluidchamber. A fluid reservoir 515 is disposed within the casing and influid communication with the fluid chamber. In certain embodiments, thecartridge 500 will also include a second reservoir 530 that is disposedwithin the casing 510 and adjacent to the fluid chamber 520.

The automated pipettor is positioned on a robot arm contained in anautomated biochemical analyzer. The automated pipettor is adapted toexecute a retrieval and dispense protocol for conducting biochemicalreactions. The retrieval and dispense protocol may be performed by acontroller (not shown) electrically connected to the robot arm and/orthe automated pipettor to retrieve a portion of the reagent from thecartridge 500 and dispense the portion of the reagent into one or morewells of the multi-well tray 400, 700 or into one or more receptacles.The retrieval and dispense protocol may then be repeated for automateddispensing of the reagent into each of remaining wells of the multi-welltray 400.

In one exemplary embodiment, the automated pipettor will receive acommand to perform automated actions required for performing anautomated reagent-based assay. The automated pipettor is then moved bythe robot arm to a position over an unused pipette tip 310 and islowered to enable frictional attachment thereto. Once the automatedpipettor, having the pipette tip 310 attached thereto, is raised suchthat the pipette tip 310 is not obstructed by additional unused tipsand/or other components within the automated biochemical analyzer, therobot arm moves the automated pipettor into a designated position over acartridge 500. The automated pipettor is thereafter lowered into thefluid chamber of the cartridge 500. If present, a frangible sealcovering the fluid chamber is punctured by the pipette tip 310. Theautomated pipettor then withdraws a predetermined amount of diluent andis raised such that the pipette tip 310 is unobstructed by the cartridge500 and/or other components within the automated biochemical analyzer.

The robot arm then moves the automated pipettor into a designatedposition over a spatially indexed multi-well tray 400 and then lowersthe pipettor such that the pipette tip 310 punctures a frangible seal440 (if present) covering a well 430 disposed in the card insert 420attached to the base 410 of the multi-well tray 400. The diluent is thendeposited into the well 430 containing a lyophilized reagent 495 used inthe reagent-based assay. Optionally, the automated pipettor willrepeatedly aspirate and the dispense the liquid contained in the well430 to allow sufficient time and fluidic pressure required toreconstitute the lyophilized reagent 495. The automated pipettorthereafter collects the reconstituted reagent and withdraws the pipettetip 310 from the well 430 of the multi-well tray 400 such that thepipette tip 310 is unobstructed by the well 430 and/or other componentswithin the automated biochemical analyzer. The robot arm then moves theautomated pipettor into a second designated position over the spatiallyindexed multi-well tray 400. The second position is selected inaccordance with the set 435 of wells to which the well 430 of the cardinsert belongs. The automated pipettor is then lowered into a well 416containing a receptacle 100, which may or may not contain a sampleundergoing analysis. Optionally, when a sample undergoing analysis ispresent in the receptacle 100, the automated pipettor will repeatedlyaspirate and then dispense the liquid contained in the receptacle 100 toallow sufficient time and fluidic pressure required to mix the contentsof the receptacle 100 within the well 416, thereby creating a reactionmixture.

After optional mixing, the automated pipettor withdraws the pipette tip310 from the well 416, but leaves the reaction mixture within thereceptacle 100. The robot arm then moves the automated pipettor to alocation over a waste receptacle and ejects the pipette tip 310. Afterejection, the robot arm moves the automated pipettor to a thirddesignated position over the spatially indexed multi-well tray 400. Thethird position is selected in accordance with the set 435 of wells towhich the first and second wells belong. The automated pipettor is thenlowered into the third well 415 containing a cap 200 to enablefrictional attachment thereto. Once the automated pipettor having thecap 200 attached thereto is raised such that the cap 200 is notobstructed the well 415 and/or other components within the automatedbiochemical analyzer, the robot arm moves the automated pipettor intothe second designated position over the well 416 containing thereceptacle 100 containing the reaction mixture. The automated pipettoris then lowered such that the cap 200 is securably attached to thereceptacle 100 as described above. As the automated pipettor withdrawsfrom the well 416, the capped receptacle attached thereto is withdrawnfrom the well 416 of the multi-well tray 400 for transport to, forexample, a thermocycler for automated incubation.

In another exemplary embodiment, the automated pipettor will receive acommand to perform automated actions required for performing anautomated reagent-based assay. The automated pipettor is then moved bythe robot arm to a position over an unused pipette tip 310, and islowered to enable frictional attachment thereto. Simultaneously, priorto, or after such movement, a transport mechanism, such as a rotarydistributor (not shown) within the biochemical analyzer attaches to anarm 720 of a multi-well tray 700 and transports the multi-well tray 700to a predetermined position for use in the analysis.

Once the automated pipettor, having the pipette tip 310 attachedthereto, is raised such that the pipette tip 310 is not obstructed byadditional unused tips and/or other components within the automatedbiochemical analyzer, the robot arm moves the automated pipettor into adesignated position over a cartridge 500. The automated pipettor isthereafter lowered into the oil chamber 530 of the cartridge 500. Ifpresent, a frangible seal covering the oil chamber 530 is punctured bythe pipette tip 310. The automated pipettor then withdraws apredetermined amount of oil and is raised such that the pipette tip 310is unobstructed by the cartridge 500 and/or other components within theautomated biochemical analyzer.

The robot arm then moves the automated pipettor into a designatedposition over a spatially indexed multi-well tray 400 and/or over areceptacle 100, and the pipettor is lowered such that the pipette tip310 enters the open end 145 thereof. The oil is then dispensed into thereceptacle 100. Optionally, the procedure of withdrawing oil from theoil chamber 530 of the cartridge 500 is repeated one or more times,depending on the number of reactions to be performed.

Thereafter, the automated pipettor withdraws the pipette tip 310 fromthe receptacle 100, and the robot arm moves the automated pipettor to alocation over a waste receptacle and ejects the pipette tip 310. Afterejection, the robot arm moves the automated pipettor to a position overa second unused pipette tip 310 and lowers the pipettor to enablefrictional attachment thereto. Once the automated pipettor, having thesecond pipette tip 310 attached thereto, is raised such that the pipettetip 310 is not obstructed by additional unused tips and/or othercomponents within the automated biochemical analyzer, the robot armmoves the automated pipettor into a designated position over a secondreceptacle 100 having therein a sample for analysis, and is lowered suchthat the pipette tip 310 enters the open end 145 thereof. The sample isthen collected from the second receptacle and transferred to the firstreceptacle 100. It should be understood that in certain embodiments, thesample will have been previously dispensed into the receptacle prior todeposit of the oil and/or the sample for analysis may be transferredfrom a material transfer unit (not shown) within the biochemicalanalyzer. After depositing the sample into the first receptacle, theautomated pipettor withdraws the pipette tip 310 from the receptacle100, and the robot arm moves the automated pipettor to a location over awaste receptacle and ejects the pipette tip 310. After ejection, therobot arm moves the automated pipettor to a position over a third unusedpipette tip 310 and lowers the pipettor to enable frictional attachmentthereto.

Once the automated pipettor having the third pipette tip 310 attachedthereto is raised such that the pipette tip 310 is not obstructed byadditional unused tips, and/or other components within the automatedbiochemical analyzer, the robot arm moves the automated pipettor intothe second designated position over the cartridge 500 and lowers thepipettor into the fluid chamber 520 of the cartridge 500. If present, afrangible seal covering the fluid chamber 520 is punctured by thepipette tip 310. The automated pipettor then withdraws a predeterminedamount of diluent and is raised such that the pipette tip 310 isunobstructed by the cartridge 500 and/or other components within theautomated biochemical analyzer.

The robot arm then moves the automated pipettor into a designatedposition over a spatially indexed multi-well tray 700 and lowers thepipettor such that the pipette tip 310 punctures a frangible seal (ifpresent) covering a well 715 disposed in the multi-well tray 700. Thediluent is then deposited into the well 715 containing a lyophilizedreagent 495 used in the reagent-based assay. Optionally, the automatedpipettor will repeatedly aspirate and dispense the liquid contained inthe well 715 to allow sufficient time and fluidic pressure required toreconstitute the lyophilized reagent 495.

The automated pipettor thereafter collects the reconstituted reagent andwithdraws the pipette tip 310 from the well 715 of the multi-well tray700 such that the pipette tip 310 is unobstructed by the well 715 and/orother components within the automated biochemical analyzer. The robotarm then moves the automated pipettor into the designated position overthe first receptacle 100 containing the dispensed oil and sample foranalysis. The automated pipettor is then lowered into the open end 145of the receptacle 100 to dispense the reconstituted reagent. Optionally,the automated pipettor will repeatedly aspirate and dispense the liquidcontained in the receptacle 100 to allow sufficient time and fluidicpressure required to mix the contents of the receptacle 100, therebycreating a reaction mixture.

After optional mixing, the automated pipettor withdraws the pipette tip310 from the receptacle 100, but leaves the reaction mixture within thereceptacle 100. The robot arm then moves the automated pipettor to alocation over the waste receptacle and ejects the pipette tip 310. Afterejection, the robot arm moves the automated pipettor to a designatedposition over a well 415 containing a cap 200 to enable frictionalattachment thereto. Once the automated pipettor having the cap 200attached thereto is raised such that the cap 200 is not obstructed thewell 415 and/or other components within the automated biochemicalanalyzer, the robot arm moves the automated pipettor into the designatedposition over the receptacle 100 containing the reaction mixture. Theautomated pipettor is then lowered such that the cap 200 is securablyattached to the receptacle 100. As the automated pipettor is raised, thecapped receptacle is lifted from a receptacle holder or well of amulti-well tray 400 for transport to, for example, a centrifuge and/orthermocycler for automated incubation.

In certain embodiments, it is desirable to expedite the process ofreconstitution of the lyophilized reagent 495, mixing of the reagentwith the test sample, and subsequent capping of the receptacle 100containing the reagent mixture. In such embodiments, more than one robotarm and automated pipettor may be provided within the automatedbiochemical analyzer, and may be independently controlled to expand thecapabilities thereof. Alternatively, or in addition thereto, theautomated biochemical analyzer may include one or more pick and placerobots, which may be used to perform functions not related to collectionand/or deposit of liquids, such as capping of a receptacle 100containing a reaction mixture and/or transport of the capped receptacleto a centrifuge and/or thermocycler for automated incubation.

Although the present disclosure has been described with reference to theabove example, it will be understood that modifications and variationsare encompassed within the spirit and scope of the disclosed subjectmatter. Accordingly, the present disclosure is limited only by thefollowing claims.

What is claimed is:
 1. A method for reconstituting a lyophilizedreagent, the method comprising the steps of: (a) drawing a diluent intoa pipette tip attached to an automated pipettor; and (b) dispensing thediluent into a reagent well containing a lyophilized reagent andincluding at least one retention feature on an internal wall of thereagent well for retaining the lyophilized reagent within the reagentwell.
 2. The method of claim 1, further comprising, after step (b), thestep of aspirating and dispensing the contents of the reagent well oneor more times with the automated pipettor to produce a reconstitutedform of the reagent, wherein the aspirating and dispensing occur withinthe reagent well.
 3. The method of claim 2, further comprising, afteraspirating and dispensing the contents of the reagent well one or moretimes, withdrawing at least a portion of the reconstituted reagent fromthe reagent well and transferring the withdrawn reconstituted reagent toa different receptacle.
 4. The method of claim 1, wherein a frangibleseal is affixed to a top surface of the reagent well and covers an openupper end of the reagent well, and further comprising, prior to step(b), the step of puncturing the frangible seal with a pipette tip. 5.The method of claim 1, wherein the retention feature comprises a collarfixed to the internal wall at or proximal to an open upper end of thereagent well.
 6. The method of claim 5, wherein the collar comprises oneor more fingers extending into the reagent well toward an axial centerof the reagent well.
 7. The method of claim 1, wherein the retentionfeature comprises an annular ridge formed on the internal wall andpositioned above the lyophilized reagent.
 8. The method of claim 1,wherein the retention feature comprises a spiral channel formed along alength of the internal wall and positioned above the lyophilizedreagent.
 9. The method of claim 1, wherein the retention featurecomprises a tapered ring attached to the internal wall and positionedabove the lyophilized reagent.
 10. The method of claim 1, wherein the atleast one retention feature comprises a set of longitudinally extendingand circumferentially-spaced rigid guides projecting radially from theinternal wall.
 11. The method of claim 1, further comprising step (c)after step (b), withdrawing a reconstituted form of the reagent from thereagent well and transferring the reconstituted reagent to a differentreceptacle.
 12. The method of claim 11, wherein the retention featurecomprises one or more fingers extending into the well toward an axialcenter of the well, and wherein step (c) comprises inserting the pipettetip into the reagent well and contacting the fingers with the pipettetip and causing the fingers to flex toward the internal wall, therebyallowing the pipette tip to pass therethrough.
 13. The method of claim11, wherein the at least one retention feature comprises a set oflongitudinally extending and circumferentially-spaced rigid guidesprojecting radially from the internal wall, and wherein the rigid guidesdirect a pipette tip toward the axial center of the well as the pipettetip is lowered therein.
 14. The method of claim 11, wherein the reagentwell includes one or more features formed in a bottom wall of thereagent well to facilitate the deposit and/or collection of a fluid fromthe reagent well, and step (c) comprises contacting the features with anend of a pipette tip inserted into the reagent well and thus prevent theend of the pipette tip from making sealing contact with the bottom ofthe reagent well.
 15. The method of claim 14, wherein the featurescomprise one or more of one or more grooves, a pair of crisscrossedgrooves, one or more ridges, an annular ridge, and a plurality of bumps.16. The method of claim 1, wherein the retention feature defines anopening that is smaller than a diameter of the lyophilized reagent, suchthat the retention features retain the lyophilized reagent within thereagent well, wherein the opening is sized to permit an end of a pipettetip to be inserted into the well.